The overall objective of this project is to develop techniques and ultimately a system which will allow the rapid, objective and quantitative analysis of brain scan data obtained from computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). This entails relating the scans to a computer based atlas of the human brain for objective determination of anatomic information with which to relate the functional image. We plan to develop a system with "user friendly software" (e.g. simple to use by clinicians and basic researchers). We expect that the system will be highly interactive and will provide real-time analytic feedback abilities to the user. Techniques will be developed for the interactive display, manipulation, and image processing of 3-D data. A 3-D Voxel representation of a standard Atlas of the human brain as well as of clinical CT, MRI or PET data will be implemented. Image processing capabilities will include automatic thresholding, reslicing in any arbitrary plane, calculation of various statistics, and highlighting outlines or areas of interest. The display capabilities will include real-time translation, rotation, scaling, segmentation, and enhancement of 3-D medical objects. Interactive editing of such 3-D medical objects and the merging of multiple modalities (i.e., CT and MRI) for comparison and analysis will also be supported.